The overall goal of this SCOR proposal is to develop and conduct clinical trials to correct congenital diseases of the human hematopoietic stem cell. The central theme of the research plan is the development of new methods of cellular and transduction gene therapy for these diseases. Specifically, we will develop new methods for stem cell transplantation across HLA barriers and will attempt to treat Fanconi Anemia and Diamond-Blackfan Anemia by replacement gene therapy protocols for these diseases. Dr. Guinan's project will focus on new advances in the biological and clinical aspects of haplomismatch bone marrow transplantation. Several projects will focus on the basic biology of Fanconi Anemia and Diamond- Blackfan Anemia and on Retroviral Transfection Scale-Up and Phase I gene therapy protocols for bone marrow transplantation. Other projects will focus on the continued development of retroviral and lentiviral programs which fortify our clinical efforts. In Dr. Mulligan's project, the capacity of bone marrow stem cells to replace diseased muscle cells will be explored while Dr. Sodroski's project will investigate the adaptations of HIV that will permit the virus access to human cells. The strength of this proposal lies in its focused drive toward clinical experimentation while gathering data of basic importance and exploring new frontiers.